The present invention relates to a cartridge for a typing ribbon with a blocking element, comprising a container in which a ribbon supply reel is rotatable and a blocking element acting between the reel and the container to prevent the reel from winding when the cartridge is not mounted on a typewriter or other typing machine.
A cartridge is known, in which a blocking element is inserted in a groove or channel disposed in the container in the region of the supply reel, so as to act between the lower part of the cover and the upper edge of the ribbon, thus compressing the supply reel against the bottom of the container. The blocking element thus prevents the typing ribbon from unwinding when that is not wanted. If however the user operates the manual forward feed disc, rotating it can cause the ribbon to feed forward, with a certain amount of difficulty. The known cartridge, with the specific blocking element, suffers from the disadvantage that, if the user is not paying attention, he can fit the cartridge to a machine with the blocking element still in position. The ribbon feed devices of the machine thus cause rotary movement and forward feed of the ribbon. However, since the supply reel is subjected to friction and restrained or checked, in the long run problems occur such as excessive wear of the ribbon feed device, as well as the possibility of breakage of the ribbon and the device itself.